Low-power digital radio as a ubiquitous subscriber loop

The recent growth in the use of digital radio is reviewed. The technology used to implement low-power digital radio in the local exchange loop plant is discussed. The integration of digital radio subscriber loops withnetwork intelligence is explored. The relationship between low-power digital radio loops and broadband fiber loops is briefly examined, and standards and frequency allocation activities are summarized     

Sharing in teams of heterogeneous,collaborative learning agents

This paper is focused on the effects of sharing knowledge and collaboration of multiple heterogeneous, intelligent agents (hardware or software) which work together to learn a task. As each agent employs a different machine learning technique, the system consists of multiple knowledge sources and their respective heterogeneous knowledge representations. Collaboration between agents involves sharing knowledge to both speed up team learning, as well as refine the team's overall performance and group behavior. Experiments have been performed that vary the team composition in terms of machine learning algorithms, learning strategies employed by the agents, and sharing frequency for a predator‐prey cooperative pursuit task. For lifelong learning, heterogeneous learning teams were more successful than homogeneous learning counterparts. Interestingly, sharing increased the learning rate, but sharing with higher frequency showed diminishing results. Lastly, knowledge conflicts are reduced over time the more sharing takes place. These results support further investigation of the merits of heterogeneous learning. © 2008 Wiley Periodicals, Inc.     

IMPLEMENTING THE IS ARCHITECTURE

The implementation of an enterprisewide information systems architecture to direct systems development can be hindered by the traditional IS organizational structure. By reassessing the IS department and realigning its structure, companies can remove barriers to the implementation of an IS architecture approach. This article presents a model that can form the basis for an organizational structure tailored to the environment of any IS department.     

LROC analysis of detector-response compensation in SPECT

Localization ROC (LROC) observer studies examined whether detector response compensation (DRC) in ordered-subset, expectation-maximization (OSEM) reconstructions helps in the detection and localization of hot tumors. Simulated gallium (Ga-67) images of the thoracic region were used in the study. The projection data modeled the acquisition of attenuated 93- and 185-keV photons with a medium-energy parallel-hole collimator, but scatter was not modeled. Images were reconstructed with five strategies: 1) OSEM with no DRC; 2) OSEM preceded by restoration filtering; 3) OSEM with iterative DRC; 4) OSEM with an ideal DRC; and 5) filtered backprojection (FBP) with no DRC. All strategies included attenuation correction. There were four LROC studies conducted. In a study using a single tumor activity, the ideal DRC offered the best performance, followed by iterative DRC, restoration filtering, OSEM with no DRC, and FBP. Statistical significance at the 5% level was found between all pairs of strategies except for restoration filtering and OSEM with no DRC. A similar ranking was found for a more realistic study using multiple tumor activities. Additional studies considered the effects of OSEM iteration number and tumor activity on the detection improvement that iterative DRC offered with respect to OSEM with no DRC.     

Housing quality and childrenȁ9s socioemotional health

This study examined whether the socioemotional health of children 9–12 years old is related to the physical quality of their residence and neighborhood. The study included 95 children from households with a wide range of incomes in a medium-sized anglophone and a medium-sized francophone Canadian city. Each childȁ9s socioemotional health was assessed and the quality of each childȁ9s housing was assessed on up to 309 aspects of the residence and immediate neighborhood, based on walk-throughs and interviews with the parents in the residences. The childrenȁ9s socioemotional health, as assessed by their parents, was worse when the physical condition of their residenceȁ9s interior, exterior, and immediate neighborhood was worse. This relation remained significant after controlling for household income, parental education and mental health status, the childȁ9s gender, and time lived in the residence. Furthermore, none of these five factors moderated the relation, evidence for its robustness.     

Chronic and temporary distinct expectancies as comparison standards: Automatic contrast in dispositional judgments.

In 4 studies, the authors examined whether making outcome expectancies distinct resulted in their use as comparison standards and, consequently, in contrastive dispositional inferences for a target's behaviors. The expectancies examined were based on either chronic future-event expectancies (Study 1) or temporary, manipulated expectancy standards (Studies 2–4). Analyses revealed that when contextual expectancies were distinct or separable from target information, participants' dispositional judgments were contrasted from them under cognitive load and overcorrected (assimilated to them) under no load. These effects were mediated by participants' behavior categorizations. Evidence suggestive of a proceduralized form of correction for task difficulty and an effortful awareness-based correction for the effects of expectancies also were found. Results are examined in light of recent models of the dispositional inference process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A three-dimensional analysis of coextrusion

The coextrusion of two polymers in a square channel is presented in this paper. Fluids are fed into the channel through different passages with a plane separating them partway through the channel. Downstream of the separation plane, the streams merge forming an interface between them, which is normally distorted before reaching the exit of the channel. These results show that the degree of distortion depends upon factors in addition to the ratio of the viscosity of the two fluids. The ratio of the flow rates in addition to the shape and location of the separation plane are also important.     

Chronic and temporarily activated causal uncertainty beliefs and stereotype usage.

In 3 studies, we examined the hypothesis that the effects of stereotype usage on target judgments are moderated by causal uncertainty beliefs and related accuracy goal structures. In Study 1, we focused on the role of chronically accessible causal uncertainty beliefs as predictors of a target's level of guilt for an alleged academic misconduct offense. In Study 2, we examined the role of chronic causal uncertainty reduction goals and a manipulated accuracy goal; in Study 3, we investigated the role of primed causal uncertainty beliefs on guilt judgments. In all 3 studies, we found that activation of causal uncertainty beliefs and accuracy concerns was related to a reduced usage of stereotypes. Moreover, this reduction was not associated with participants' levels of perceived control, depression, state affect, need for cognition, or personal need for structure. Results are discussed in terms of their implications for the model of causal uncertainty and, more generally, in terms of the motivational processes underlying stereotype usage. (PsycINFO Database Record (c) 2010 APA, all rights reserved)